My work focuses on groundwater flow, and its effect on natural systems. This research uses a variety of approaches such as numerical modeling, ion and isotope chemistry, tracers, parameter estimation, and stochastic methods. It emphasizes a range of groundwater – surface water systems including wetland, stream, and lake interactions. More recently this work has been extended to research investigating ecohydrology of aquatic systems, effects of climate and landuse drivers, and source and transport of enteric viruses to drinking water wells and through watersheds.

CURRENT PROJECTS

Trout Lake WEBB project

Groundwater Recharge project

Great Lakes Water Availability Pilot

Black Earth Creek ground-water/surface-water modeling

Other project and science support, teaching, and outreach as requested

EDUCATION

Ph.D in Hydrogeology (major) and Wetland Sciences (minor) - University of Wisconsin-Madison, 1993

Research Fellow, US DOE, Environmental Restoration and Waste Management Program (Aug. 1991 - Dec. 1993) I worked in Wisconsin and at the Idaho National Engineering Laboratory. I initiated and conducted a study to apply stable isotope techniques to investigate the hydrology of the Eastern Snake River Plain, Idaho.

Science and Products

The TC Chamberlin Modeling Center provides one-stop access to advanced computing so no project is limited by a lack of computer power. The Center can provide hardware access, assistance with migration and implementation, and training. We also develop, test, and disseminate state-of-the-art computational and analytical techniques and tools so models can be more effectively used in decision-...

USGS initiated the Water, Energy, and Biogeochemical Budgets (WEBB) program to understand the processes controlling water, energy, and biogeochemical fluxes over a range of temporal and spatial scales, and the effects of atmospheric and climatic variables. Trout Lake is one of five small, geographically and ecologically diverse watersheds representing a range of hydrologic and climatic...

Large amounts of data are being generated that require hours, days, or even weeks to analyze using traditional computing resources. Innovative solutions must be implemented to analyze the data in a reasonable timeframe. The program HTCondor (https://research.cs.wisc.edu/htcondor/) takes advantage of the processing capacity of individual...

The PEST++ software suite is object-oriented universal computer code written in C++ that expands on and extends the algorithms included in PEST, a widely used parameter estimation code written in Fortran. PEST++ is designed to lower the barriers of entry for users and developers while providing efficient algorithms that can accommodate large, highly parameterized problems.

PESTCommander is an object-oriented Graphical User Interface (GUI) written in Python® that facilitates the management of model files ("file management") and remote launching and termination of slave computers across a distributed network of computers ("run management").

GENIE is a model-independent suite of programs that can be used to generally distribute, manage, and execute multiple model runs via the TCP/IP infrastructure. The suite consists of a file distribution interface, a run manage, a run executer, and a routine that can be compiled as part of a program and used to exchange model runs with the run manager.

The U.S. Geological Survey’s Soil-Water-Balance (SWB) code was developed as a tool to estimate distribution and timing of net infiltration out of the root zone by means of an approach that uses readily available data and minimizes user effort required to begin a SWB application. SWB calculates other components of the water balance, including soil...

The fractured Silurian dolomite aquifer is an important, but vulnerable, source of drinking water in northeast Wisconsin (Sherrill in Geology and ground water in Door County, Wisconsin, with emphasis on contamination potential in the Silurian dolomite, 1978; Bradbury and Muldoon in Hydrogeology and groundwater monitoring of fractured dolomite in...

Groundwater resources information was needed to understand regional aquifer systems and water available to wells and springs for rearing important Lake Michigan fish species at the Kettle Moraine Springs State Fish Hatchery in Sheboygan County, Wisconsin. As a basis for estimating the groundwater resources available, an existing groundwater-flow...

The duration of winter ice cover on lakes varies substantially with climate variability, and has decreased over the last several decades in many temperate lakes. However, little is known of how changes in seasonal ice cover may affect biogeochemical processes under ice. We examined winter nitrogen (N) dynamics under ice using a 30+ yr dataset from...

The Community for Data Integration (CDI) represents a dynamic community of practice focused on advancing science data and information management and integration capabilities across the U.S. Geological Survey and the CDI community. This annual report describes the various presentations, activities, and outcomes of the CDI monthly forums, working...

Water quality affects many aspects of water availability, from precluding use to societal perceptions of fit-for-purpose. Pathogen source and transport processes are drivers of water quality because they have been responsible for numerous outbreaks resulting in large economic losses due to illness and, in some cases, loss of life. Outbreaks result...

A new groundwater flow model was created for Dane County, Wisconsin, to replace an earlier model developed in the 1990s by the Wisconsin Geological and Natural History Survey (WGNHS) and the U.S. Geological Survey (USGS). This modeling study was conducted cooperatively by the WGNHS, the Capital Area Regional Planning Commission, and the USGS....

A new groundwater flow model for Dane County, Wisconsin, replaces an earlier model developed in the 1990s by the Wisconsin Geological and Natural History Survey (WGNHS) and the U.S. Geological Survey (USGS). This modeling study was conducted cooperatively by the WGNHS and the USGS with funding from the Capital Area Regional Planning Commission (...

A groundwater-flow model was developed for the Bad River Watershed and surrounding area by using the U.S. Geological Survey (USGS) finite-difference code MODFLOW–NWT. The model simulates steady-state groundwater-flow and base flow in streams by using the streamflow routing (SFR) package. The model was calibrated to groundwater levels and base...

Models of groundwater systems help to integrate knowledge about the natural and human system covering different spatial and temporal scales, often from multiple disciplines, in order to address a range of issues of concern to various stakeholders. A model is simply a tool to express what we think we know. Uncertainty, due to lack of knowledge or...

A groundwater/surface-water model was constructed and calibrated for the Black Earth Creek watershed in south-central Wisconsin. The model was then run to simulate scenarios representing common societal concerns in the basin, focusing on maintaining a cold-water resource in an urbanizing fringe near its upper stream reaches and minimizing...

IntroductionThrough the Science Strategy for Highly Pathogenic Avian Influenza (HPAI) in Wildlife and the Environment, the USGS will assess avian influenza (AI) dynamics in an ecological context to inform decisions made by resource managers and policymakers from the local to national level. Through collection of unbiased scientific information on...

The PEST++ software suite is object-oriented universal computer code written in C++ that expands on and extends the algorithms included in PEST, a widely used parameter estimation code written in Fortran. PEST++ is designed to lower the barriers of entry for users and developers while providing efficient algorithms that can accommodate large, highly parameterized problems.

PESTCommander is an object-oriented Graphical User Interface (GUI) written in Python® that facilitates the management of model files ("file management") and remote launching and termination of slave computers across a distributed network of computers ("run management").

GENIE Version 2 is a model-independent suite of programs that can be used to generally distribute, manage, and execute multiple model runs via a TCP/IP network. The suite consists of a file distribution interface, a run manager, a run executer, and a routine that can be compiled as part of a program and used to exchange model runs with the run manager.